Appearing in our office on opposite sides of a weekend, Speck's ToughShell ($50) and iFrogz's BullFrog ($35) for iPhone 4 are both geared towards the same market -- in fact, the cases have quite a bit in common. Both combine hard plastic shells and soft rubber exteriors in an effort to compete with the likes of OtterBox's Defender and Griffin's Survivor, only at lower prices. Yet even given their overall similarities, there are significant differences in their execution, and neither is claiming military-grade protectiveness. Color is another factor: ToughShell is only available in black-on-black, while BullFrog comes in black/green, orange/black, and silver/black variations.

It’s pretty clear after handling ToughShell that this new case—released more than a year after the only iPhone that sits inside—was one of those challenging, “keep on tweaking ‘til we get it right” designs. It’s considerably more advanced than Speck’s earlier ToughSkin which effectively added a thick rubber cover to a simple plastic snap-on interior frame. Here, a hinged two-piece hard plastic case is held together and gasketed with a thick, ribbed rubber edge, capable of covering all of the iPhone 4’s buttons, ports, and switches, while permitting limited access to the latter two through flip-open rubber pieces. It’s really tough to get to the side switch unless you have very skinny fingers, but for users who want tons of protection, the extra rubber is appreciated.

ToughShell’s plastic is rather thick and feels particularly nice. It covers the whole of the back, as well as the front bezel. There are very well-tailored holes for both cameras, the ambient light sensor, and earpiece, as well as a rubber cover over the Home button. A little more pressure is required to press the Home button than normal, but not much. Like most cases that come all the way up to the edge of the screen, we found typing with two thumbs to be somewhat more difficult, and it may wind up being harder to access Notification Center on the upcoming iOS 5 without room to swipe from the top. Also included with ToughShell are a piece of screen protector film and a rotating belt clip that can double as a viewing stand; both are unremarkable, but as extras, they’re welcome.

Whereas ToughShell is fused together into one inseparable unit, BullFrog is comprised of two distinctly separate layers. The first is a hard plastic slider-style case that’s lined with a soft, velvety material. While iFrogz claims that this core can be used separately, it’s doesn’t look or feel great on its own, and we wouldn’t recommend it. The rubber is a different story. While certainly thicker, it feels much more complete, and the ribbed-edge outer layer stays in place via strategically placed pegs around the edges of the plastic frame.

There are dedicated covers for the Sleep/Wake and volume buttons, as well as flip-open covers for the headphone and Dock Connector ports. Unlike ToughShell, BullFrog doesn’t incorporate any sort of protector over the side switch. It is, however, much easier to access. Much like Speck’s case, there is significant protection around the glass touchscreen display. There’s a combined opening for the earpiece and front-facing camera, another for the ambient light sensor, and a Home button cover that’s a lot easier to press.

Arguably the most unique feature in BullFrog is the plastic sliding cover that can protect the rear camera and flash. The overall opening is about an inch and a quarter long, with the actual slider coming in at a little bit more than half an inch. Ideally, it slides with just a little bit of pressure to reveal the camera when it’s needed. In our testing, however, it was very difficult to get it out of the closed position—pretty much impossible without wedging a fingernail in and really forcing it. Even when freed, it did not move very smoothly at all. It’s a good feature on paper that’s less than satisfying in practice.

For $35, BullFrog is otherwise a real value; it’s the least expensive case we’ve seen in the ultraprotective category. No, it doesn’t include a belt clip, but that’s an accessory we barely see in use these days anyway, and similarly, while the case certainly doesn’t feel cheap, it falls short only when compared to considerably more expensive cases such as ToughShell. While the lack of side switch coverage isn’t a big deal when compared to the rest of the case’s protectiveness, the camera cover may be a problem for some users. With the cover left in the open position, BullFrog is as protective as most iPhone 4 cases, but when it’s closed, it can be hard to open in time to grab that important shot. The so-so implementation of a useful feature brings an otherwise great case down to a “very good” B+ rating.

On the other hand, ToughShell feels more polished, but at $50, it’s also more expensive. We really liked the use of the hinged design, the nice integration of different materials, and pretty remarkable coverage. The only notable downside is the fact that it’s rather difficult to access the side switch, and by reference to the same-priced OtterBox and Griffin’s cases, it relies upon film rather than integrated screen coverage. As between Defender, Survivor, and ToughShell, we’d call it a draw: all three cases are worthy of B+ rating. If you’re looking for the one the feels best in your hand, that distinction goes to ToughShell. Defender is sleekest of the bunch, and Survivor has the most rugged aesthetic, plus camera protection. In deciding between them, it really comes down to personal preference.

Editors' Note: iLounge only reviews products in "final" form, but many companies now change their offerings - sometimes several times - after our reviews have been published.
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